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  • The Earth is covered in living things.

  • From very large organisms to the tiniest creatures, all living things on Earth have one thing

  • in common: they cannot survive alone.

  • To grow and flourish, living things need the support of an ecosystem.

  • An ecosystem is what we call all the things that interact in a specific area, both living

  • and non-living.

  • Ecosystems can be hard to define.

  • They are interconnected in many ways, and it is not always easy to see where one ecosystem

  • ends and another begins.

  • Different ecosystems may look very similar, or very different from one another, but all

  • ecosystems are made of the same basic parts.

  • Ecosystems have both living and non-living parts.

  • The non-living parts of an ecosystem include things like sunlight and temperature, air

  • and wind, the types and amount of water available, and rocks and soil.

  • The living parts of an ecosystem are the plants and animals in it.

  • The non-living parts of an ecosystem combine to create the conditions that will determine

  • what kinds of living things will be able to survive there.

  • You won't find a coral reef in the desert or cactus in the ocean, because the conditions

  • are wrong for them to live and grow.

  • There are three main types of living things in an ecosystem: producers, consumers, and

  • decomposers.

  • Producers produce, or make, their own food.

  • Usually, they make their food from sunlight through photosynthesis.

  • Plants are the most obvious example of producers.

  • Without producers, no animals would be able to survive.

  • That's because all animals are consumers, and need to consume or eat their food.

  • Some animals, called herbivores, get their energy from eating plants.

  • Other animals, called carnivores, get their energy from eating other animals.

  • There is a third group of animals called omnivores.

  • Omnivores get their energy by eating both plants and meat.

  • Humans are an example of omnivores!

  • Finally, there are the decomposers.

  • Decomposers are generally bacteria and fungi.

  • They consume dead plants and animals and break them down into nutrients that are released

  • into the soil.

  • These nutrients are used by producers like plants to help them grow, and the cycle begins

  • all over again.

  • The living things inside an ecosystem form a community.

  • Within the community are many different populations.

  • A population is made of all the members of one specific species.

  • For instance, all of the plants and animals on the savanna make up the savanna community.

  • Within the savanna, all of the zebras make up the zebra population, all of the acacia

  • trees make up the acacia tree population, and all of the lions make up the lion population.

  • All the parts of an ecosystem must work together to reach a balance that allows each of the

  • members of the system to thrive.

  • For example, in a balanced ecosystem predators keep the population of rabbits from growing

  • too large because when there are too many rabbits they eat too many plants.

  • If rabbits ate too many plants, the plants would not be able to grow back fast enough,

  • and other animals that need the plants would not have enough to eat.

  • Without enough plants the animals that depend on them for food would start to die, and the

  • soil begins to erode, or wash away, which makes it harder for new plants to grow in

  • the future.

  • Ecosystems can become imbalanced when something disrupts their normal workings.

  • Anything from bad weather to diseases to an erupting volcano can disturb an ecosystem.

  • Human activity can also damage the balance of of natural ecosystems.

  • By cutting down trees and clearing forests, building roads and cities, killing some animals,

  • introducing new ones, or creating pollution, it can become impossible for the plants and

  • animals in an ecosystem to grow and thrive.

  • In most cases, ecosystems can recover and regain a healthy balance if given enough time

  • and an opportunity to rest from whatever disturbed them in the first place.

  • Since people rely on ecosystems for food and resources, it is important that we try to

  • protect them.

  • Fortunately, there are many ways to have a positive impact on your local ecosytem!

  • By doing anything from picking up trash, planting a tree, conserving water and electricity,

  • or creating a habitat for wild animals, you can help the ecosystem around you become happier

  • and healthier.

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子供のための生態系を理解する。生産者、消費者、分解者 - フリースクール (Understanding Ecosystems for Kids: Producers, Consumers, Decomposers - FreeSchool)

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    薛明璟 に公開 2021 年 01 月 14 日
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